OpenVPN Quickstart
While this HOWTO will guide you in setting up a scalable client/server VPN using an X509 PKI (public key infrastructure using certificates and private keys), this might be overkill if you are only looking for a simple VPN setup with a server that can handle a single client.
Static key advantages
Simple setup.
No X509 PKI (public key infrastructure) to maintain.
Static key disadvantages
Limited scalability — one client, one server.
Lack of perfect forward secrecy — key compromise results in total disclosure of previous sessions.
Secret key must exist in plaintext form on each VPN peer.
Secret key must be exchanged using a pre-existing secure channel.